Floor



Jan. 1, 1929. 19691979 H. M. KNIGHT HNEY .Jan..1, 1929. 1,697,070

H. M. KNIGHT l 43 IN VEN TUR H Meri' M. 151913902? Patented Jan. l,1929.

HERBERT M. KNIGHT, OF MONTGLAIR, NEW JERSEY.

FLOOR.

Application filed August 10, 1921.

My invention relates to improvements in floors and has particularreference to floors of precast concrete units of cellular type.

One of the objects of my invention is to produce a floor of cellularpre-cast concrete which is of the cantilever type. Another ohject of theinvention is to produce a cellular, cantilever type pre-cast floor,having a lloating floor resting upon and filling the space betweenopposite cellular units. A further object of the invention is to producesuch a cellular, cantilever type of floor, with provisions therein forthe location of electric and other channels or appliances, without thenecessity of making openings or altera tions in the units. Still anotherobject of the invention is to provide a unit, pre-cast floor upon whicha wearing flooring can be laid without the necessity of introducing`rough flooring. Yet another object of the invention is the production ofa floor constructed of pre-cast units the underside of which shall beflat. A further object is to provide a floor of pre-cast units whichshall not require the use of loor beams or girders. Another object is toproduce a floor constructed of precast units which shall not require theintroduction of forms during any portion of the installation. Stillanother object of the invention is to produce a floor constructed ofpre-cast units which can be installed in connection with walls ofpre-cast materials. Still a further object is to produce a floor ofpre-cast units in which, due to the division of the floors intocantilevers supporting a cent-ral float-ing section, the stresses andbending moments will be re'- duced to a. minimum, and below what wouldbe the corresponding stresses and bending moments in a floor, the spanof which would be the distance between the two opposite points ofsupport. Other objects of the invention will appear from the followingdescription and the accompanying drawings.

The accompanying` drawings, Figs. 1 `tor 9 inclusive, are illustrativeof the invent-ion and indicate the usual and preferred embodimentthereof. rlhey are however illustrative only and are not to beconsidered as illustrative of all types in which the invention may beembodied, nor as exclusive of other types than that indicated.-

l illustrate my invention by the accompanying drawings in which Fig. 1is a cross section of a floor on the line 1 1 of Fig. 2.

Serial No. 491,225.

Fig. 2 is a. longitudinal section on the line 2 2 of Fig. 1. Fig. 3 is aplan view on the linel 3 5-lof Fig. 1. Fig. l is an enlarged section ofa joint between wall plates resting upon a floor. Fig. 5 is an enlargedcross-sec tional view of a joint between the floor units. Fig. 6 is aplan view of the floating floor unit on the line 6 6 of Fig. 7. Fig. 7is a crossssection of a floating lloor unit on the line 7 7 of Fig. 6.Fig. Sis a top plan view of a ceiling plug for use with this type ofpre-cast floor, on the line 8 8 of Fig. 9 and 9 is a crosssection ofsuch a ceiling plug on the line 9 9 of Fig. 8.

Referring to the drawings in which similar figures refer toi-similarparts. A pre-cast floor slab 1 projects from and is supported by innerpre-cast bearing-wall slabs 2 and outer wall slabs 3 and al. Thebearing-wall slabs are in multiple and are connected together by the key5, while the exterior wall slabs are connected together by the key 6.Both outer a-nd bearing-wall slabs have thickened edges 7 around theirperimeterswith key-ways 8 in the vertical edges for the insertion of thekeys 5 and 6. Shoulders 9 are formed upon the upper surfaces of thethickened edges of the supporting slabs and elongated holes 10 passthrough said edges. Nut housings 11 are cast in the back of thesupporting slabs,positioned to receive and hold a nut 12 before theassembling of the supporting slabs, and to facilitate the entra-'nce ofa bolt 13 into said nut after the assembling of the slabs. TWashers 14with elongated holes therein are interposed between said shoulders andsaid nuts. limer superimposed pre-cast bearing-wall slabs l5 rest upon.the floor units 1 and outer pre-cast wall slabs 16 and 17 aresuperimposed upon the outer end of the unit 1 above the slabs 3 and l.The said slabs 15, 16 and 17 have thickened peripheral edges 18 and keys5 and 6 unite together the units composing the outer and inner wallsrespectively. Shoulders 19 are formed upon the upper surfaces of thehorizontal thickened 'edges of the superimposed wall slabs and elongatedholes 20 pass through said horizontal edges. Windows 21 are left openduring the casting of the superimposed wall slabs through which tointroduce the bolt 13 and through which also to place and tighten thenut 22 upon the bolt 13. Alillongated holes 23 pass through the floorunit 1 so positioned as to register with the holes 10 in the lower, orsupporting slab and holes 20 in the upper or superimposed slab,theresult of the screwing of the bolt 13 into the housed nut 12 and ofthe tightening of the nut 22 upon the washers 24 having an elongatedhole 25 therethrough, is to permanent-- ly fasten together thesupporting-and superimposed slabs and the floor unit and to hold thecantilever floor unit suspended horizontally from the said walls.Vlongues 2G are formed upon thel lower face of the floor unit adapted torest in grooves 2T in the upper horizontal thickened edges of thesupporting slabs, and tongues 2S are cast in the lower thickened edgesof the superimposed slab adapted to engage grooves 29 cast in the upperface of the floor unit, such tongues 26 and 28 `and such grooves 27 and29 serving to position the iioor slabs. Cells 30 are formed in the bodyof the floor unit l with ribs 3l separating the said cells and frontdams 32 and rear dams 33 closing the same. Apertures 3l pass through thefront dam and apertures through the rear dam for the passage of `wiresor pipes. Pins 36 project upwardly from the front dam registering withholes 37 in the pre-cast oating section 38. Nailing strips 39 areembedded in the pre-cast floating section and an insert Ll() iscastint-o t-he lower face thereof. A ledge 4l projects from thecantilev-er floor slab adapted to receive and support a ceiling plug l2having an overlapping edge 43 and a perforation lat therein. Grooves 45are cast in the edges of the cantilever Hoor slab, which, when alined,permit of the insertion of a key 46 along the edges of the uxt-aposediioor units. A librile layer 47 covers the cells 30 and the medial ri'bs3l with anchors i8 attaching said librile layer to said ribs. Adeadening layer i9 is interposed between the ibrile layer and a wearinglayer 50.

In the usual srocess of erecting building composed in whole or in part'of reinforced concrete it is customary, in the case of the floors andthe roofs, to erect a temporary forming, covering the entire floor orroof area., and to pour mass concrete upon the temporary forming soerected, which said forming is subsequently removed when the concreteshall have hardened sutliciently to permit such removal. Such floors`are usually of the slab type of construction, either of beam and girderor of flat slab form, and are solid. For the purposes of lightness andeconomy void spaces are sometimes created within the floor slab by theintroduction, in advance of the pouring of the concrete, of cellularelement-s, either of terra-cotta, iron, or similar materials, which,being surrounder by the mass concrete during the placing thereof, areembedded in the mass, thereby creating a cellular form of iioor or roofconstruction. But all of these types or variations in floor or roofconstruction are mass floors or roofs, that is, they are created 'by thepouring of mass or liquid concrete upon. a temporary forming, eitherwith or without means for producing lightness and securing economy.

Such methods lead to great waste due to the use of large quantities oflumber in the temporary forming and its supporting means, and alsoconsume a large. amount of time of skilled and high priced labor in therect-ion of this forming. lt is evident that the temporary forming hasno use as a part of the permanent structure, and, that it has to beerected and demolished for every floor and for the roof, if it be ofconcrete, Unless an excessive amount of lumber is employed, suficient toprovide at one time for the forming for all of the lloc 5, deh ys ensuewhile waiting for the floor or floors previusly poured to set upsulliciently to permit of the safe removal of the forming thereonemployed, a loss of time which, when represented in money, may be verygreat. As it is necessary to retain the skilled labor employed informing operations during the enforced delay, and to employ themoftentimes on other and less remunerative activities, it is seen thatthe process of pouring mass concrete floors is one in which great delaysand undesirable and often prohibitive costs are almost sure to occur.Again, both because of the character of the concrete and the usualexposure of the beams and girders and when it is desired to have a flatceiling, it is necessary to add such al ceiling below the door slab orto plaster the entire lower face thereof in order to secure asatisfactory appearance. When the floor is installed in a. structure ofthe steel skeleton type, these delays and excess costs are somewhatreduced due to the ability to suspend the temporary forming from thesteel members, but the cost of the steel is heavy and such constructionis only adapted to use in tall and expensive buildings.

This invention seeks to remove and overcome the foregoing mentioneddeft-arts by means of apre-east unit type of floor or roof which isinstalled in the building without the necessity of temporary forming,permitting of the immediate introduction of the floor or roof and itsfastening in position, allowin of construction to proceed withoutinterruption, delay or unremunerative costs. The units, of which theHoor is composed, are pre-cast, that is, the concrete is poured inadvance of the location of the slab or unit in its position in the flooror roof, the unit, after hardening, being lifted to and secured in finallocation in the floor or roof. lt is apparent that this ype ofconstruction requires only an initial form, which, due to the unitsbeing in all respects similar, can be used indefinitely withoutdestruction and that units can be produce-1l indefinitely andcontinuously Without Waste or expensive delays.

kIn the usual types of prelast floors, the.

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units are solid, no provision being made to secure lightness by the useof vo-id or cellular producing means. Such units are cumbersome andheavy to handle, and often, because of the length of the span required,prohibitive in practice. ln order to obviate these apparent defects inpre-cast iioor units, a cellular type of unit is employed, cavities orvoids being formed in the body of' the unit by the use of voidproducing` means, which being of very light weight material may beallowed to remain in the unit after it shall have been poured or cast. Asufliciency ot' concrete to give the necessary strength in compressionis used in the base and in the division between the cells, and thereinforcing steel so distributed in the medial ribs as to obtain the reequired strength in tension. A very light and strong type of constructionresult-s, and one which can be economically and expeditiouslyconstructcd. Provision is made by means of' apertures through theterminal walls of' the cells 'for the passage of electric wires, pipes,etc., a form ol' construction which removes the necessity of enclosingelectric or other wiring in conduits or other lire protective channels,

Due to the fact that the usual type of floor or root construction is aslab continuous between supports, upon which it rests at either end,stresses are set up which while detern'iinable, are high. These stressesare reduced when a cantilever type of floor, divided and supporting afloating section is ein aloyed. rlhe combination of' such a cantilevertype ol' a cellula-r section, results in the strongest and lightest formof construction, such combination being` that illustrated and describedin this invention. ln the case ot a simple slab, either continuous ornon-continuous over supports, con'ipression exists in the top of theslab and tension in the bottom, this tensile stress being resisted bythe steel reinforcement introduced in the bottoni ot the slab for thatpurpose. ln the casel oit the pre-cast cant-ilever unit these stressesare reversed, that is, the top of the unit is in tension and the bottomin compression. Due to this distribution of the stresses it is possible,with the cellular form of construction, to provide for their resistancewith the greatest facility. rlhe bottom of the unit being a solid layerof concrete resists the. compressive stresses set up therein, while thetensile stresses are met by the reinforcen'icnt embedded in the upperportion of the medial ribs between the cellular elements. Again, as themaxim um bending moments are at the point oli support, it i possible toeasily increase the amount ofreintorcement in the top oit the medialribs at this point, to meet these augmented stresses, without carryingit 'throughout the entire length of' the unit, and a. great economy inthe use ol steel results. n

In the type of' cellular cantilever floor unit illustrated twoconjunctive means are used to secure the slab at the points ol support.The units are perforated, permitting the passage of a bolt, which, byengaging suitably positioned shoulders, either below the unit, or

both aboveand below, secure it i'n position and protect it against anoverturning moment around its point of support. In addi# tion to and inconjunction with this positive holding down means, the walls above thepoint of support rest upon the end ol the floor slab unit, and by theirweight constitute an additional means of securing the unit to itslsupport.

In this invention the cantilever units constituting the floor cover onlya portion of the floor or roof area, and in no inst-ance is the lengthof a. unit hall of the floor span. Therefore the weight borne directlyby va unit is never one-half of the floor loads and weights of thefloorI area which it is tributary to, and consequently the weight bornedirectly by the individual unit and transmitted directly by it to thepoint of support is comparatively small. A gap is purposely introducedbetween the separated ends of the floor units, so that the units onopposite sides of the opening act independently, all stresses reachingor arising upon one of the units be` ing transmitted directly to itspoint of support, the two units and two `points of support actingindependently, and not in conjunction as is the case with a single orcontinuous beam spanning the opening between supports.

The opening between the separated canti lever units is closed by afloating floor section resting upon a ledge cast in the outer edge ofthe supporting unit, and having holes along two of' the opposite edgesof the floating section positioned to receive projecting pins cast intothe supporting unit, which pins, by the subsequent cementing up of theholes serve to retain the floating section accurately and immovably uponthe cantilever unit, and, while not modifying the action of the floatingunit in its character of a simple slab supported at either end by thecantilever unit, aid in the transmission of the weight carried by thefloating unit to the cantilever unit and through it to the point ofsupport. rl`he span of the floating section always being small itsthickness can be materially reduced below the thickness required in aslab which spans the entire distance between the primary points ofsupport, and also the amount of reinforcing steel is reduced. The netresult is a. large reduction in the amount ol material required for thefloating member with a consequent large reduction in its weight and11;;A

an accompanying reduction in the amount of reinforcement, conditionswhich make for economy both in the floating unit and in the cantileverunit by which it is supported. A further feature of the floating unit isthe lala) Cil casting thereinto during its pouring of an ,insert of woodor similar material, upon the undersurface thereof as it is positionedin the tloor for the attachment of lighting or other fixtures which itmay be designed to suspend from the ceiling below the said door. ispreviously mentioned, apertures are provided in the ends of the cells ofthe cantilever units so that it is possible to suspend connection boxesfrom the insert en the lower side of the iioating unit and to lead wiresthereto from the walls through the cells of the cantilever units, and,in view of the incombustible character of all of the material employed,and to dispense with Ywire conduits.

The cellular cantilever units are coi ed with an extending ledge on thelow a adjacent to the gap or opening between ti said cantileversections, upon which ledg rests a ceiling plug` of concrete or similarmaterial, designed to close the lower side of the opening between thecantilever units and to present an even, flat effect. rlhis plug may beperforated, as indicated, for the purpose of introducing therethroughlighting or other devices which may be suspended :trom the ceiling.

The covering of the cells of the cantilever units need not be of acharacter to resist either tensile or con'ipressive stresses, as suolistresses are resisted by the concrete and reinforcement below the topsof the mid-ribs separating the cells. Accordingly the cells are coveredwith a material of lesser strength than that of stone, gravel or cinderconcrete, and, preferably, as indicated, by a concrete composed in partof fibrous material, which will admit of nails or similar fasteningsbeing driven therein, thereby attachingl the Wearing floor of Wood orsimilar material to the concrete floor units, an intermediate layer ofpaper or other desired insulating material being introduced between theWearing floor and the concrete units. Metal or other tics are employedto insure the adherence of the fibrous concrete to the concrete makingup the body of the cantilever units.

lVhile a floor system of such floating and cantilever units isapplicable to any form of lfiuilding construction which offers a meansof satisfactorily and securely anchoring the units to the walls or othersupport, the system has been particularly designed for use in connectionwith a system of unit concrete construction in which pre-castconcreteWall slabs or units are employed. Such construction as is here indicatedconsists in the use of double Walls of slabs provided with thiolire-,ned edges around the peripheries thereof, such thicken ingproviding a shoulder against which a nut or washer can rest. Elongatedholes for the passage of bolts perforate these thickened edges atpredetermined points. Similar holes pass through the cantilever floorslabs, the

backs of which slabs extend beyond the face of the wall and aresupported upon the thickened edges of the wall units below the floor.@ther wall units are superimposed upon the floor units in position, and,the bolt holes of the supporting and superimposed wall units and theholes in the Hoor units being in regis* tration, bolts are introduced,passing through said registering` holes, and, by the tightening of nutsupon said bolts upon Washer plates in contact with the upper and undershoulders of the thickened edges of the wall units, the whole structureis fastened permanently together. Such, and so many floors, as also theroof, may thus be installed in a building, and light and strongcharacter of construction secured.

lllhile in the above described system of construction, unconnected floorunits are of feasible employment, it is desirable, in order to secure astronger and more regular floor, to connect the adjacent cantileverunits. Such connection is made by means of a key, cemented in a key-Way,or re-entrant groove which is cast in the lateral edges of the tloorunits during their pouring. The lateral edges of the floor units are allsimilarly provided with such re-entrant grooves, which, being broughtinto juxtaposed alinement, when the units are erected in position,permit of a key! being inserted thereinto, connecting the adjacent floorunits, and by the use of cement mortaiin said grooves, fastening thesaid adjacent units together, resulting in all of the units on the sameside of the central gap acting ,as one.

For the purpose of securing, so far as it may be possible in a unit typeof structure, a monolithic construction, the wall units are fastenedtogether by keys, inserted and cemented into keyways cast in thethickened edges of the Wall units. Such uniting of the Wall units inconnection with the holdingdown bolts which imite the wall and floorslabs results in a structure in which all portions act together insustaining pressures and in supporting weights.

For the purpose of accurately and rapidly positioning the wall and floorunits, tongues and grooves are cast in the contact faces thereof, which,by their registration, serve to immediately and accurately locate theseveral wall and fioor units during assembly.

Such a system of pre-cast floors or roofs, erected without the use oftemporary constructions, in which, for the double purpose of ease inassembling and for increase of strength, a gap is interposed betweenopposing sections, such gap being bridged by a Vfloating section restingupon the inner edges of the supporting sections, the supporting sectionsbeing of cellular type, retained in position by the conj unctiveoperation of holding-down bolts and superimposed wall seclltl tions,permits of rapid and continuous construction and results in a very lightand strong type of iioor or roof.

What I claim is l. In a building construction, the combination oit'walls and iioors constructed of precast units, marginal port-ions offloor units adjacent to the walls being .inserted between upper andlower wall units, and means secured in pre-cast portions of the upperand lower wall units, said means extending through pre-cast portions ofthe floor unit whereby the upper and lower wall units cooperate with thesaid means to provide the entire support Jfor said floor unit.

2. In a building construction, the combination of walls and iioorsconstructed of precast units, marginal portions of floor units adjacentto the walls being inserted between upper and lower wall units, andbolts secured in pre-cast portions of the upper and lower wall units,said bolts extending through precast portions oit' the iioor unitwhereby the upper and lower wall units cooperate with the said bolts toprovide the entire support for said floor unit.

3. In a floor system, a multiple of pre-cast cellular floor units, awall supporting one end of said units, thickened edges on the upperportion of said supporting wall, a wall superimposed upon said units andabove said supporting wall, thickened edges on the lower portion of saidsuperimposed wall and bolts passing through said thickened edges of saidsupporting and superimposed walls and through said units.

t. In a Floor system, a multiple of prewcast cellular iioor units, meanssupporting one end of said units, thickened edges on the upper portionof said supporting means, a body superimposed upon said units and abovesaid supporting means, thickened edges on the lower portion of fsaidsuperimposed body,

`means insertible afterassembly of said parts tying said supportingmeans and said super'- imposed body and said units together, saidsuperimposed body having apertures, said apertures being contiguous toand above said tying means enabling said tying means to be invertedafter assembly of the parts.

5. In a ioor system, a multiple of precast cellular floor units, meanssupport-ing one end of said units, thickened edges on the upper portionof said supporting means, a body superimposed upon said units and abovesaid supporting means, thickened edges on the lower portion of saidsuperimposed body, bolts tying said supporting means and saidsuperimposed body and said units together and nuts embedded in saidsupporting body upholding and retaining said tying means.

6. In a floor system, a multiple of precast cellular floor units, meanssupporting one end of said units, thickened edges on the upper portionof said supporting means, a

body superimposed upon said units and above said supporting means,thickened edges on the lower portion of said superimposed body, meansytying said supporting means and said superimposed body and said unitstogether and positioning means locating said units relative to saidsupporting means and to said superimposed body,

7. In a Hoor system, a multiple of pre-cast cellular floor units, meanssupporting one end of said units, lthickened edges on the upper portionof said supporting means, other floor units and other supporting meanshaving thickened upper edges oppositely disposed to said units andsupporting means, the combined length of said oppositely disposed unitsbeing less than the total distance between said oppositely disposedsupporting means, bodies superimposed upon said oppo sitely disposedunits and above said oppositely disposed supporting means, saidsuperimposed bodies having thickened edges on the lower portionsthereof, means tying said supporting and superimposed bodies throughsaid thickened portions and said units together, and floating sectionsspanning the opening between the unsupported ends oit' said oppositelydisposed units, said sections being supported by said units.

8. In a loor system, a multiple of pre-cast cellular iioor units, meanssupporting one end of said units, thickened edges on the upper portionof said supporting means, other floor units and other supporting meansoppositely disposed to said units and said supporting means, thecombined lengths of said oppositely disposed units being less than thetotal distance between said oppositely disposed supporting means, bodiessuperimposed upon said oppositely disposed units and above saidoppositely disposed supporting means, said superimposed bodies havingthickened edges on the lower portions thereof, means tying saidsupporting and said superimposed bodies and said units together,Floating sections spanning the opening ybetween the unsupported ends ofsaid oppositely disposed units, said sections being supported by saidunits and positioning means locating said units and said sectionsrelative to each other.

9. In a floor system, a multiple of precast cellular iioor units, meanssupporting one end of said units, other floor units and other supportingmeans oppositely disposed to said units and said supporting means, thecombined length of said oppositely disposed units being less than thetotal distance between said oppositely disposed supporting means, bodiessuperimposed upon said oppositely disposed units and above saidoppositely disposed supporting means, means tying said supporting andsaid superimposed bodies and said units together, ribs in said units,front dams in said units, pins em" bedded in said ribs and in said dams,a iioating section spanning the opening between the unsupported ends ofsaid oppositely disposed units and depressions in said floating sectionregistering with an telescoping upon said pins,

10. In a floor system, a multiple of precast cellular floor units,grooves in the longitudinal edges of said units, said grooves ofjuxtaposed units being in alinement, keys in said grooves, meanssupporting one end of said units and said supporting means oppositelydisposed to said units and said supporting means, the combined lengthsof said oppositely disposed units being less than the total distancebetween said oppositely disposed supporting means, bodies superimposedupon said oppositely disposed units and above said supporting means,means tying said supporting and said superimposed bodies and said unitstogether and floating sections spanning the opening between theunsupported ends of said oppositely disposed units, said sections beingsupported by said units.

11. In a floor system, the combination of a multiple of pre-castcellular Hoor units, grooves in the longitudinal edges of said units,said grooves of juxtaposed units being in alinement, keys in saidgrooves, means supporting one end of said units, thickened edges on theupper portion of' said supporting means, other floor units and othersupporting means oppositely disposed to said units and said supportingmeans, the combined lengths of said oppositely disposed units being lessthan the total distance between said oppositely disposed supportingmeans, bodies superimposed upon said oppositely disposed units and abovesaid supporting means, said superimposed bodies having thickened edgeson the lower portion thereof, means tying said supporting and saidsuperimposed bodies and said units together and fioating sectionssupported by said units and spanning the opening between theunsupporting ends of said oppositely disposed units.

12. In a floor system, the combination of a multiple ot pre-castcellular floor units, ribs between said cells, front dams to said cells,rear dams to said cells, sides to said units, alined re-entrant groovesin the juxunits and said supporting means, the combined length of saidoppositely disposed supporting means, bodies superimposed upon saidoppositely disposed units, means tying said supporting and saidsuperimposed bodies and said units together and floating sectionsspanning the opening between the unsupported ends of said oppositelydisposed units and resting upon said units and ceiling plugs beneathsaid oating sections supported by said units.

13. In a floor system, the combination of a multiple of pre-castcellular floor units, ribs between said cells, front dams to said cells,rear dams to said cells, sides to said units, alined re-entrant groovesin the juxtaposed sides of adjacent units, keys in said aligned grooves,means supporting one end of said units, other floor units and othersupporting means oppositely disposed to said units and said supportingmeans, the combined length of said oppositely disposed units being lessthan the total distance between said oppositely disposed supportingmeans, bodies superimposed upon said oppositely disposed units, meanstying said supporting and said superimposed bodies and said unitstogether, 'floating sections spanning the opening between theunsupported ends of said oppositely disposed units and resting upon saidunits, ridges upon the unsupported ends of saidv units and ceiling plugsresting upon said ridges.

Signed at New York, in the county of New York and State of New York,this ninth day of August A. D. 1921.

HERBERT M. KNIGHT.

